A short-lived hoax on Twitter briefly erased $200 billion of value from U.S. stock markets on Tuesday, underscoring the vulnerability of financial markets to computerized trading programs that buy and sell shares without human intervention.

A tweet purportedly from the Associated Press just before 1:08 p.m. reported two explosions in the White House and that President Barack Obama had been injured. The posting sent the Dow Jones Industrial Average tumbling roughly 145 points in an instant.

...

RELATED VIDEO

Five of the Costliest Tweets Ever

As the hacked post from the AP shows, tweets even move the market. Quentin Fottrell joins The News Hub with a look back at some other costly social media blunders. (Photo: Getty Images)